首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   21826篇
  免费   911篇
  国内免费   13篇
  22750篇
  2020年   253篇
  2019年   247篇
  2018年   423篇
  2017年   360篇
  2016年   384篇
  2015年   252篇
  2014年   365篇
  2013年   1577篇
  2012年   627篇
  2011年   682篇
  2010年   362篇
  2009年   443篇
  2008年   597篇
  2007年   596篇
  2006年   549篇
  2005年   483篇
  2004年   462篇
  2003年   455篇
  2002年   418篇
  2001年   803篇
  2000年   794篇
  1999年   586篇
  1998年   238篇
  1997年   213篇
  1996年   193篇
  1992年   488篇
  1991年   424篇
  1990年   487篇
  1989年   414篇
  1988年   391篇
  1987年   368篇
  1986年   390篇
  1985年   441篇
  1984年   341篇
  1983年   285篇
  1982年   223篇
  1979年   323篇
  1978年   261篇
  1977年   207篇
  1976年   204篇
  1975年   302篇
  1974年   346篇
  1973年   351篇
  1972年   274篇
  1971年   241篇
  1970年   208篇
  1969年   229篇
  1968年   290篇
  1967年   251篇
  1966年   273篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
961.
Multiple personality is a dissociative hysterical condition in which there are two or more autonomous personalities. Historically multiple personality has been viewed as an oedipal conflict. Case studies, however, indicate the importance of preoedipal dynamic issues as well. Both ego splitting and oedipal repression seem to be the basic defense mechanisms. The depressive position, in which there is integration of good and bad objects, has not been reached. Objects are split on the basis of sex in that the mother is seen as all bad, while the father is seen as all good. Multiple personality can be considered to occupy a position between oedipal and preoedipal development.  相似文献   
962.
Ingmar Pörn 《Studia Logica》1983,42(2-3):293-298
In the paper I investigate aspects of adverbial modification as an operation applying an adverb or adverbial phrase to a predicate and thereby creating a new predicate. The logic of adverbial modification, on this view, belongs to the logic of predicate modifiers. The theory I present is intended to cover not only adverbial modification but also attributive modification, but problems concerning the latter will not be given any special attention.  相似文献   
963.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
964.
Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.  相似文献   
965.
966.
967.
Two kinds of causal inference rules which are widely used by social scientists are investigated. Two conceptions of causation also widely used are explicated — the INUS and probabilistic conceptions of causation. It is shown that the causal inference rules which link correlation, a kind of partial correlation, and a conception of causation areinvalid. It is concluded anew methodology is required for causal inference.  相似文献   
968.
Four baboons (Papio cynocephalus) were tested using food as reward for ear advantages in the monaural discrimination of pure tones, three-tone musical chords, synthetically constructed consonant-vowels, and vowels. All four animals showed highly significant and reproducible ear advantages for each class of acoustic stimulus with marked individual differences in the direction of their ear asymmetry. The results obtained in these experiments represent the first evidence of ear asymmetries for different classes of acoustic stimuli in a nonhuman species. Further, the ear advantages found in these animals under monaural conditions resemble those obtained with dichotic presentation in human subjects and thus suggest that the baboon may be a valuable model of central auditory processing of various types of acoustic stimuli in man.  相似文献   
969.
This study examined the effects of different concurrent verbal memory loads on a recognition accuracy task using bilaterally presented nouns. Four different memory load conditions were examined. They varied along a size dimension of either three or six words and along a complexity dimension of either easy concrete nouns or difficult highly abstract nouns. In each of the above conditions and in one control group, order or word report was controlled and in a second control group subjects were free to report the lateralized words in any order they wished. There were 20 subjects in each of the six groups. As expected, a significant right visual field superiority for verbal processing was obtained. there were no main effects of size of memory load nor complexity of m emory load on the laterality patterns. More subtle fluctuations in the patterns were found in the form of significant interactions between memory load, order of word report, and visual field. These interaction effects suggest that words reported second in the bilateral task, are more susceptible to the interfering effects of either larger or more complex memory loads. This is particularly true for right visual field words. While these data generally support a structural model of hemispheric organization, the interaction effects suggest that modifications must be made to the basic model to account for such factors as hemispheric capacity limits and order of report in the bilateral task.  相似文献   
970.
Attentional biases and the right-ear effect in dichotic listening   总被引:2,自引:0,他引:2  
Most dichotic listening experiments permit subjects to deploy attention in any way they choose. We argue that this adds uncontrolled variance to the observed right-ear advantage. In the first experiment, more robust laterality effects were obtained in an identification task with focused than with divided attention. Such differences were not found in the second experiment, when a detection procedure was used. Virtually all the laterality effect observed in the second study could be attributed to subjects who were biased attenders, in the sense that they exhibited more intrusions from the right ear to the left than vice versa. However, rather than indicating that laterality effects are simply attentional bias, this effect can be attributed to an asymmetry of perceptual discrimination.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号